Bedbugs were sprayed but they still bite: what should I do? - briefly
When insecticide treatment fails, add thorough laundering, mattress and box‑spring encasements, and arrange professional heat or steam treatment to eradicate surviving bugs. Inspect and seal cracks, then monitor regularly to confirm complete elimination.
Bedbugs were sprayed but they still bite: what should I do? - in detail
If chemical treatment has been applied and the bites continue, the infestation has not been eliminated. The following actions are required to achieve control.
First, verify that the insects are still present. Examine seams, folds, and crevices of mattresses, box springs, headboards, and furniture. Use a flashlight and a magnifying lens to locate live bugs, shed skins, or dark spots (fecal stains). Capture any specimens for identification.
Second, assess the effectiveness of the spray. Many products do not penetrate deeply into fabric or reach hidden harborages. Residual insecticides can lose potency after a few weeks, especially if the area is heavily soiled. If the label indicates a short residual period, plan for a repeat application according to the manufacturer’s schedule.
Third, supplement chemical control with non‑chemical measures:
- Wash all bedding, curtains, and removable fabrics in hot water (≥ 60 °C) and dry on high heat for at least 30 minutes.
- Encase mattresses and box springs in certified bed‑bug‑proof covers; keep them sealed for a minimum of one year.
- Reduce clutter that provides hiding places; vacuum floors, upholstery, and cracks thoroughly, then discard the vacuum bag in a sealed container.
- Apply heat treatment to infested items: expose objects to temperatures of 45–50 °C for several hours, or use a professional steam device that reaches at least 100 °C for a few seconds per surface.
- Consider using diatomaceous earth or silica gel dust in cracks and voids; these desiccants kill bugs on contact without chemicals.
Fourth, engage a licensed pest‑management professional if the problem persists after the above steps. Professionals can perform:
- Targeted inspections with trained detection dogs or specialized traps.
- Whole‑room heat treatment, raising ambient temperature to 50–55 °C for 4–6 hours, which eradicates all life stages.
- Fumigation with proven gas formulations when heat is impractical.
- Integrated pest‑management plans that combine chemical, physical, and monitoring techniques.
Fifth, implement ongoing monitoring. Place interceptor cups under each leg of the bed and furniture; check them weekly and record captures. Replace traps as needed and maintain cleanliness to prevent re‑infestation.
Finally, educate household members about early signs of activity and proper hygiene practices. Prompt reporting of new bites or sightings enables rapid response and reduces the likelihood of a resurgence.